Suture or Prosthetic Reconstruction of Experimental Diaphragmatic Defects

Diaphragmatic reconstruction may cause several respiratory changes. The aims of the present study were to evaluate the respiratory changes induced by two methods of diaphragmatic reconstruction. Two groups of rats with an experimental diaphragmatic defect were studied. In one group (n = 5), diaphragmatic resection was followed by stitching together the borders of the wound (SUT); in another group (n = 5), the defect was repaired by suturing in a polytetrafluoroethylene (PTFE) patch. All animals were sedated, anesthetized, paralyzed, and mechanically ventilated. Spirometry, respiratory mechanics, and thoracoabdominal morphometry were evaluated before and after diaphragmatic reconstruction. The suture of the diaphragm significantly decreased FVC and FEV1, and increased respiratory system, lung, and chest wall static and dynamic elastances and viscoelastic/inhomogeneous pressures in relation to their respective control values. On the other hand, diaphragmatic reconstruction with PTFE increased only respiratory system, lung, and chest wall static elastances. In addition, respiratory system, pulmonary, and chest wall viscoelastic/inhomogeneous pressures and dynamic elastances, as well as respiratory system and lung elastances, were significantly greater in SUT than in PTFE. Lateral diameter at the level of the xiphoid and cephalocaudal pulmonary diameter diminished only in the SUT group. The reconstruction of the diaphragm with PTFE might be preferred to simple suture for surgical repair of large diaphragmatic defects, at least from a mechanical standpoint.